Air-cooled wall construction for incinerators



A. R. OLSEN April 30, 1968 AIR-COOLED WALL CONSTRUCTION FOR INCINERATORSFiled June 13, 1966 Y h d a 2 m J a T w I/ M a (a m x 4% J1 6 4 w I M tk M J W A w {1i United States Patent 3,380,409 AIR-COOLED WALLCONSTRUCTION FOR INCINERATORS Arnold R. Olsen, Brooklyn, N.Y., assignorto Dresser Industries, Inc., Dallas, Tex., a corporation of DelawareFiled June 13, 1966, Ser. No. 557,311

9 Claims. (Cl. 110-56) ABSTRACT OF THE DISCLOSURE The present inventionrelates to air cooled wall construction for use in incinerators. Theconstruction consists of an outer wall, structural members verticallysecured to the interior of the wall, for example, I-beams, and arefractory wall composed of multiple courses of cylindrical refractorytile aligned vertically to provide continuous air passages through thecourses and air inlet means for the air passages.

Many of the present day municipal incinerators employ a storage pit,bridge crane and grab bucket for the charging of refuse into thefurnaces. The major distinction between types of furnaces is that someare batch fed and others employ a continuous feed.

.The batch fed furnaces usually do not exceed 150 tons per day capacity.These employ a hydraulically or electric motor driven charging gatepositioned over the roof of the furnace and are further divided, usuallyinto circular grate or rectangular grate furnaces. End furnace chargingis used in some industrial and municipal rectangular grate furnaces.

0n incinerators handling above 50 tons of refuse per day, there isincreasing tendency to use furnaces of the continuous feed type. Theimprovements in refractory;

and in the furnace equipment are making it possible in many cases todepend on single unit installation. Types of continuous feed furnacesare the traveling grate, the reciprocating grate plus rotary kiln typeand the continuous or constant flow types using sections ofreciprocating or rocking grates with vertical offset between sections.

In either type of incinerator construction, the vessel may becharacterized as consisting of an outer metal shell or structuralsupport member having a refractory lining or enclosure adjacent thereto.The refractory enclosures are a vulnerable part of the incinerator unit.They must tolerate the high temperatures required for completecombustion and withstand the operating conditions of abrasion, slagerosion, flame impingement and thermal shock. Therefore, it is apparentthat this important part of the unit demands in its engineering design aproper coordination of layout, structure, and materials to provide along life at low cost.

It is among the objects of the present invention to provide an aircooled wall construction for incinerators.

Other objects of the invention will in part appear hereinafter.

In order to more fully understand the nature and objects of the presentinvention, reference should be had to the following detailed descriptionand drawings in which:

FIG. 1 is a schematic elevation view of a portion of a typicalcontinuous feed incinerator;

FIG. 2 is a plan view of an air cooled wall construction according tothe teachings of the invention; and

FIG. 3 is a side elevation view of a wall construction.

Briefly, according to one embodiment of the present invention there isprovided an air cooled wall construction for use in refuse and wasteincinerators. Among other things, the construction comprises an outershell (which may "be composed of metal, masonry, asbestos,

etc.) to which there are secured a plurality of structural members atspaced intervals. The structural members may be characterized generallyas having opposed flanges separated by a connecting bar. Preferably, theconnecting bar is intergral with the flanges. One of the flanges iscontiguous with the shell and the opposed flange projects therefrom in avertical direction. A refractory wall fabricated of a plurality ofcourses of hollow refract ry tile extend vertically, adjacent the shelland spaced therefrom. A suitable insulating material, if desired, may belodged between the wall and a metal shell. Certain of the courses oftile envelop the projecting flanges while the remainder of the coursesare disposed between the enveloping tile to provide a unitary wallconstruction. The hollow tile in each course are aligned to provide aplurality of independent, vertical passages in the wall.

Referring to the drawings, FIG. 1 illustrates the typical travelinggrate type incinerator. The drawing shows a charging hopper 12 and achute 14. The chute from the charging hopper to the roof of the furnaceis usually about 15 feet in height. The charging hopper can be the samewidth as the grate if desired or can taper as is shown in theillustration. The chute is kept filled with refuse and acts as aneffective draft seal. The inclined ignition or traveling grate 16 takesthe refuse away from the charging hopper. The radiant heat from thefurnace walls 18 causes a rapid ignition of the waste. The burningmaterial cascades off the end of this first grate 16 onto the horizontaltraveling or burning grate 20 which, operating at a faster speed,transport the material towards the ash dump 22. The speed of the grateis regulated to have as complete a 'burn out of the material aspracticable before reaching the residue disposal trough (not shown).Provisions are made for stoking in this type of furnace, although lessst-oking is required than with batch fed furnaces. Air is supplied forcombustion through the burning grate and through the furnace walls, forexample, through ports 24 and 26.

Referring to FIG. 2, there is shown a preferred air cooled wallconstruction. The construction consists of an outer metal shell 30 witha plurality of courses of refractory tile 32 spaced therefrom. On theinterior of the shell there are secured, as by welding, a plurality ofaligned and equidistantly spaced structural I-beams 34. One flange 36 ofthe I-beam is contiguous with the shell and the opposed flange 38projects therefrom. The courses of tileencompassing the projectingflange consists of a plurality of pairs of generally C-shaped tile 40.Each of these tile contains an outer lip 42 arranged to contact asimilar lip of the other tile in the pair, and an inner lip 44 arrangedto be in juxtaposition to the bar 46 of the I-beam connecting theflanges. The remainder of the courses of tile consist of generallyO-shaped tile 48.

It is preferred that the wall consist of alternate courses of theseC-shaped tile pairs and the O-shaped tile. However, more than one courseof O-shaped tile may be interposed between the pairs of C-shaped tile,depending on the spacing of the structural members. It is also preferredthat the refractory tile contain interlocking means, such as the tongues50 shown on the C-shaped tile and the mating grooves 52 indicated on theO-shaped tile. Other forms of interlocking means, well known to thoseskilled in the art, may be employed within the scope of the presentinvention.

The courses of tile are vertically integrally aligned to provide aunitary wall construction. The hollow tile in each course are aligned toprovide a plurality of independent, vertical, passages in the wall.

At the bottom of the wall construction, shown in FIG. 3, the lowermosttie in each course is supported on a refractory skew shape 54 on oneside, and an L-shaped structural bar 56 welded to the inner periphery ofthe porjecting flange 38. Disposed below the wall is a common conduit58, i.e., a U-shaped channel member, which opens into all of theindependent vertical passages.

Thus, during the operation of the furnace or incinerator, a positiveflow of air caused by some mechanical means, such as, a fan, could bepiped into the common conduit and would pass behind the refractory tilefaces and could be collected in a larger system than that furnishing theair to allow for expansion and then could be vented into the furnace asunderfire air or utilized in a heating system or exhausted to theatmosphere. The supporting structural members also would be air cooledin this operation.

While the invention has been described with regard to particularembodiments and examples, it should be understood that modification,substitutions and the like may be made therein without departing fromits scope.

Having thus described the invention in detail and with suflicientparticularly as to enable those skilled in the art to practice it, whatis desired to have protected by Letter Patent is set forth in thefollowing claims.

I claim:

1. An air cooled wall construction suitable for use in refuse and wasteincinerators comprising an outer shell, a plurality of structuralmembers vertically secured to the shell at spaced intervals, eachstructural member extending substantially from the top to the bottomthereof, said structural members being characterized as having opposedflanges separated by a connecting bar, one of said flanges beingcontiguous with the shell and the opposed flange being spaced therefrom,a refractory wall fabricated of a plurality of courses of hollowrefractory tile aligned vertically to form continuous air passagesthrough said courses from substantially the top to the bottom thereof,said courses being located adjacent said shell and spaced therefrom,certain of said tile enveloping and enclosing said spaced flanges withinsaid air passages, the remainder of said courses of tile being disposedbetween said enveloping tile to provide a unitary wall construction, andan air inlet means for said air passages.

2. The construction of claim 1 in which said structural members 'areI-beams.

3. The construction of claim 1 in which said structural members aresubstantially equidistantly spaced.

4. The construction of claim 1 in which said certain courses of tileconsist of a plurality of pairs of generally C-shaped tile, each of saidtile having an outer lip arranged to contact a similar lip of the othertile in said pairs and an inner lip arranged to be in juxtaposition tothe bar of said structural member when said pair of tile envelop saidprojecting flange of the structural member.

5. The construction of claim 1 in which the remainder of said courses oftile consist of generally O-shaped tile.

6. The construction of claim 1 in which said wall contains alternatecourses of C-shaped tile pairs and O-shapcd tile.

7. The construction of claim 1 which contains in addition, means forinterlocking said tile in adjacent courses.

8. The construction of claim 1 which contains in addition a commonconduit disposed below said tile wall construction, said common conduitopening into all of said independent vertical passages.

9. The construction of claim 8 in which the common conduit is a U-shapedchannel member.

References Cited UNITED STATES PATENTS 1,109,553 9/1914 Slick. 1,501,5636/ 1924 Lawrence. 1,622,431 3/1927 Feigerbaum -1 X 2,114,960 4/1938 Beal1101 2,769,410 11/1956 Over 110-1 2,915,877 12/1959 Darling 110-11,701,287 2/1929 Waite et al. 110-1A XR FOREIGN PATENTS 60,077 8/1942Denmark. 422,025 1/1935 Great Britain.

FREDERICK L. MATTESON, 111., Primary Examiner.

H. B. RAMEY, Assistant Examiner.

